Myopia (aka nearsightedness) is a common visual condition where objects/images close are clear (eg. reading, TV), but objects at a distance are blurry. The blurring effect we see is a result of when the light bouncing off objects and images into our eye are focused to a focal point in FRONT of the retina instead of ON the retina, which translates into a clear picture.
What causes Myopia?
1. Genetics
When ONE of a child’s parent is near-sighted, then they have a ~15% chance of developing myopia. When BOTH parents are myopic, then the risk of the child becoming myopic goes up to ~40%.
Myopia is hereditary but it’s not the same way as inheriting your eye colour. It is a result of a combination of genetic and environmental factors. Myopia involves many genes and inheriting these genes play a significant role in developing myopia. One study found that these genes explain up to 80% of the refractive error i.e. a person’s glasses prescription.
2. Environmental
Screen time
Research has found that children who spend more time indoors are more at risk to develop myopia. Research suggests that exposure to natural sunlight is beneficial for the development of the eyes in young children - don’t forget your UV400 sunglasses, sun screen, and brim hat! Children benefit from outdoor time for their eyes and general health. One study found that for every 1 hour a child spends outside a week, their risk of being nearsighted decreased by ~2%.
Asthenopia or Eyestrain
Children’s eyes strain when they stare at a screen for a prolonged time. It is easy for them to lose track of time and become absorbed into screen activity. At Respect, our Optometrists recommend all parents to follow the screen activity guideline by the Canadian Association of Optometrists
Did you know?
Some people experience blurred distance vision only when they’re driving at night, but not during the day time. This is called Night Myopia. There are two main causes:
Low light conditions stimulate the accommodative reflex which is normally used while reading.
The person has naturally large pupil size, which is exacerbated in low lighting. This results in a decreased depth of field making it more difficult to see at far objects.
Symptoms of Myopia:
Squinting
Headaches
Difficulty seeing distant objects (school whiteboard, road/traffic signs, etc)
Tends to hold near objects very close
Sitting close to TV
So how is Myopia treated?
Our Optometrist are able to diagnose myopia through a comprehensive exam and recommends solutions tailored to your needs.
Treatment options for myopia:
Eyeglasses - easy fix!
Contact lenses - improved over the years for better moisture and comfort. Great option if you’re active.
Refractive surgery - Dr. Steve can discuss if you’re a good candidate, which surgery opton is the best for you, and his recommended laser centre.
About the Author
Dr. Steven Hoang received his Doctor of Optometry at the University of Waterloo. He serves as the owner and full-time eye doctor of Inglewood and Ramsay at Respect Eyecare. His special interest is in contact lenses and dry eye syndrome.